1. Field of the Invention
The present invention relates to a laminating apparatus for laminating a protective film on a surface of a card, particularly, relates to a laminating apparatus mounted with an improved mechanism for controlling positional fluctuation of a protective film accurately.
2. Description of the Related Art
As a full-blown card era has come, various kinds of cards have normally been used in daily life. Such a card is, for example, a card of which surface is printed with specific information, a magnetic card such as a telephone card, and an IC card in which an IC memory chip is installed as represented by a credit card. In case of applications for identifying a person, an image such as a facial portrait of the person is printed on a surface of a card.
It is often the case that those various kinds of cards are laminated with a protective film on their surfaces so as to protect their surfaces from scratching or stain, or so as to prevent information printed thereon from being altered.
More specifically, by thermally compression bonding a transparent film in ribbon shape having a thickness of approximately 30 μm to 50 μm on a surface of a card, which was previously printed with information, the transparent film is bonded on the surface of the card and results in a protective film.
One of laminating apparatuses for conducting the laminating process is disclosed in the Japanese publication of unexamined patent applications No. 2001-105493.
The laminating apparatus disclosed in the Japanese publication of unexamined patent applications No. 2001-105493 laminates a protective body (laminating film), which is formed with a resin layer to be a protective layer on a substrate such as PET (polyethylene terephthalate), on a surface of a recording medium such as a card, which is made from plastic or wood free paper through a thermo compression bonding process by means of a heat roller, and resulting in laminating the resin layer on the surface of the card.
With respect to the other methods of laminating, there existed a method such that a substrate of a laminating film itself was bonded on a surface of a card and the substrate resulted in a protective film.
In this case, the laminating film is constituted by a substrate and an adhesive layer, and the substrate is previously cut halfway along a border line of an area to be bonded, that is, contour of a card normally.
Then, after the laminating process is conducted, a part of the laminating film, which was not bonded on a card, is separated from the laminating film such a way that the part is cut off along the halfway cut portion.
Further, there existed another type of laminating film that is formed in a roll shape (hereinafter referred to as rolled laminating film), wherein a precut patch (protective film) made of a transparent film is affixed on a carrier or board (substrate) for transportation at certain intervals. A sensor mark is marked on the carrier of the rolled laminating film so as to distinguish a position of the patch.
In a laminating apparatus, which laminates a patch on a card by using such a rolled laminating film, a sensor detects the sensor mark first before conducting a laminating operation. The laminating apparatus conducts a thermo compression bonding method, wherein a precut patch is heated while determining a position of the precut patch, the heated patch is compression-bonded on a platen roller, the patch alone is separated from a carrier, and then the separated patch is thermally compression-bonded on a surface of a card that is previously printed.
In the case of such a rolled laminating film, it is possible to laminate a patch on a card in succession.
In the meantime, in case a patch is affixed on a rolled laminating film at certain intervals, a position of each patch is almost constant with respect to a carrier. However, it possibly occurs that a position of a patch is shifted in certain degree of fluctuation across production bathes as long as a rolled laminating film is an industrial product. It is experientially known that such fluctuation is small within one roll of laminating film but rather large across respective rolls of laminating films.
With referring to FIGS. 16 and 17, description is given to positional fluctuation of a patch that is affixed on a rolled laminating film.
FIG. 16 is a pattern diagram of a rolled laminating film showing positional fluctuation of a patch in a direction of the rolled laminating film to be taken up or in a longitudinal direction of the rolled laminating film.
FIG. 17 is a pattern diagram of a rolled laminating film showing positional fluctuation of a patch in a direction intersecting at right angles to a longitudinal direction of the rolled laminating film to be taken up or in a lateral direction of the rolled laminating film.
In FIG. 16, a patch (protective film) 1203 is affixed on a carrier (substrate) 1203C at certain intervals in a longitudinal direction of the carrier 1203C.
Further, a sensor mark 1201 is provided on a side edge portion of the carrier 1203C in relation to each patch 1203.
Furthermore, in FIG. 16, doted lines 1202 denote a normal position of a patch 1203 to be affixed therein, wherein a distance from the sensor mark 1201 to the normal position of the patch 1203 is denoted by an arrow 1204, and a shifting amount of positional fluctuation of a patch 1203 in the longitudinal direction of the rolled laminating film is denoted by another arrow 1205.
In FIG. 17, a patch 1303 is affixed on a carrier 1303C at certain intervals in a longitudinal direction of the carrier 1303C as the same manner as the patch 1203 shown in FIG. 16.
Further, a sensor mark 1301 is provided on a side edge portion of the carrier 1303C in relation to each patch 1303.
Furthermore, in FIG. 17, doted lines 1302 denote a normal position of the patch 1303 to be affixed therein, wherein a distance from the sensor mark 1301 to the normal position of the patch 1303 is denoted by an arrow 1304, and a shifting amount of positional fluctuation of the patch 1303 in a lateral direction intersecting at right angles to the longitudinal direction of the rolled laminating film is denoted by another arrow 1305.
If a patch of which position is shifted from a normal position as mentioned above, is laminated on a card, then a laminating position of the patch with respect to the card is shifted across production batches.
It is commonly adopted as a method of adjusting positional fluctuation of the patch 1203 in the longitudinal direction of the rolled laminating film that a shifting amount 1205 of positional fluctuation of a patch 1203 is obtained by detecting an edge portion 1203A in the longitudinal direction of the patch 1203 by means of a sensor, and then a stopping position of the carrier 1203C or a card is controlled so as to cancel the shifting amount 1205.
On the other hand, with respect to positional fluctuation of a patch 1303 in the lateral direction, a shifting amount of positional fluctuation of a patch is approximately constant within one roll of laminating film, so that a worker visually adjusts insertion depth of a roll of a laminating film when inserting the roll into a supply reel shaft. However, such work depends upon visual estimation and experience of each worker.
Accordingly, there existed a problem such that controlling positional fluctuation through visual estimation and experience is hardly conducted in higher accuracy and stably.